1. Field of the Invention
The present invention relates to a herbal composition for improving anticancer activity, immune response and hematopoiesis of the body, and protecting the body from oxidative damage. More particularly, the present invention relates to a herbal composition comprising a first hot-water extract from a mixture of the medicinal plants Angelicae gigantis Radix, Cnidium officinale Makino and Paeonia japonica Miyabe et Takeda at an equal weight ratio, and a polysaccharide fraction as a precipitate formed by adding ethanol to a second hot-water extract from a mixture of the plants Angelicae gigantis Radix, Cnidium officinale Makino and Paeonia japonica Miyabe et Takeda at an equal weight ratio.
2. Description of the Prior Art
Cancer has been treated by directly killing cancer cells by chemotherapy with anticancer agents and radiotherapy, by surgical removal or by activating the immune system participating in the inhibition of cancer cells. In the past, the direct-killing method or surgery were mainly used in cancer therapy. Recently, cancer has been treated by immunotherapy in combination with the direct-killing method. Moreover, with advances in the understanding of the mechanisms of the immune system, much effort has been directed to the employment of immunomodulators for cancer treatment. Immunomodulators enhance the body's immunity by non-specifically stimulating the immune cells, resulting in enhanced protection against disease-causing factors. Examples of the non-specific immunomodulators include inactivated bacterial preparations, chemically synthesized compounds (synthesized nucleic acid derivatives or glycosides), and biological factors (cytokines or hormones). Studies of cancer therapies based on improving the body's immunity using the immunomodulators are in progress. However, owing to their toxicity or side effects, most of the non-specific immunomodulators are limited in their clinical applications. In particular, with the identification of cytokines participating in the immune system, active studies on the use of cytokines in cancer therapy are underway, in which cytokines are produced on a large scale by genetic engineering tools. For example, immunostimulators including interleukin-2 and tumor necrosis factor (TNF) were evaluated for their potential to be applied to cancer therapy, but were demonstrated to have severe side effects and thus have been tried within limited cases.
Hematopoiesis is the process of producing a variety of blood cells including the immune cells from the hematopoietic stem cells of bone marrow, and is closely related to the activity of the immune system. In particular, cytokines acting at each step of the differentiation of the hematopoietic stem cells into the blood cells have been recently identified, and factors inducing proliferation of the hematopoietic cells, such as the granulocyte colony-stimulating factor (G-CSF), have been actively studied to apply them to the treatment of diseases. However, to obtain therapeutic effects, they should be administered to the body in a large quantity. Moreover, in this case, severe side effects are often exhibited, thus limiting their applications.
Cancer treatment by chemotherapy or radiotherapy is accompanied by damage to the hematopoietic system and self-renewal tissues. Such side effects originate from oxidative damage to the tissues by anticancer drugs or radiation. Many efforts have been made to find substances capable of protecting the body from radiation. After the first report in 1949 that cysteine, having a thiol group, has an effect of protecting the body from radiation, research has been focused on aminothiol derivatives (particularly, WR series compounds synthesized by Walter Reed Army Hospital in Washington, D.C.). However, the aminothiol radioprotectors are limited in their clinical application owing to their toxicity. Subsequently, the radioprotective effect of chemically synthesized compounds was studied, including dipyridamole, adenosine monophosphate and deoxyspergualin, but they were also limited in practical applications owing to their severe toxicity. Other efforts to obtain radioprotective effects were made by stimulating the immune and hematopoietic systems using polysaccharides such as glucan and inactivated bacterial preparations such as the streptococcal agent OK-432. Recently, factors associated with the immune responses and hematopoietic functions, which are exemplified by immunostimulators including interleukin-1, the tumor necrosis factor (TNF), hematopoietic cell proliferation-inducing agents such as the granulocyte colony-stimulating factor (G-CSF), and hormones, have been used in studies to obtain the radioprotective effect, but, owing to their side effects, such attempts have been carried out in very limited cases.
As described above, there is an urgent need for the development of substances capable of improving the anticancer function, immune function and hematopoietic function by activating the immune system, as well as protecting the body from the side effects caused by cancer therapy such as radiotherapy. In this regard, a large number of recent studies have focused on the development of physiologically active substances having mild side effects using natural products. In particular, based on the fact that various diseases including aging and cancer are caused by oxidative damage to the body by radiation or chemical compounds as well as by harmful active oxygen species or free radicals, anti-oxidant agents have been studied for their preventive and therapeutic effects against diseases. In addition, efforts to discover physiologically active substances from natural products having the effects of regulating and protecting the body have been actively performed, and some of the discovered natural substances have been applied to food supplements for improving health or as therapeutic agents.
Research aimed at discovering immunomodulators from natural products has focused on the evaluation of the effects of natural plant components or known Chinese herbal materials, and some of the natural substances identified to have immunomodulating activity have been put to practical use. A research group in France reported that the plant Eleutherococcus senticosus has an effect of improving recovery from hematopoietic disorder caused by radiation. Also, ginseng, natural pigments, the plant Codonopsis pilosula, the plant Cnidium officinale Makino, the fungus Ganoderma lucidum, and other Chinese herbs and herbal components have been studied for their radioprotective activity, mainly in Japan, Taiwan and China.
Radiation causes disorders of the immune system and the hematopoietic system, as well as damage to the self-renewal tissues. Based on the results of researches for Chinese herbal materials with a protective effect against each symptom accompanying radiation treatment, the present inventors previously tried to find a herb combination capable of overcoming all of the symptoms following radiation treatment, resulting in the finding that a herbal composition, prepared by mixing the plants Angelicae gigantis Radix, Cnidium officinale Makino and Paeonia japonica Miyabe et Takeda at an equal weight ratio, and extracting the mixture by hot water, was safer than the conventional immunostimulating drugs. The herbal composition is disclosed in Korean Pat. Application No. 2000-23772. However, with respect to increasing the body's immune function and the hematopoietic function, the herbal composition has just 2-3-fold higher effects when compared to a control with no administration of the herbal composition, and limited effects on activation of the anticancer immune responses.